1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Generic DSI Command Mode panel driver
4  *
5  * Copyright (C) 2013 Texas Instruments Incorporated - https://www.ti.com/
6  * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
7  */
8 
9 #include <linux/backlight.h>
10 #include <linux/delay.h>
11 #include <linux/gpio/consumer.h>
12 #include <linux/jiffies.h>
13 #include <linux/module.h>
14 #include <linux/of_device.h>
15 #include <linux/regulator/consumer.h>
16 
17 #include <drm/drm_connector.h>
18 #include <drm/drm_mipi_dsi.h>
19 #include <drm/drm_modes.h>
20 #include <drm/drm_panel.h>
21 
22 #include <video/mipi_display.h>
23 
24 #define DCS_GET_ID1		0xda
25 #define DCS_GET_ID2		0xdb
26 #define DCS_GET_ID3		0xdc
27 
28 #define DCS_REGULATOR_SUPPLY_NUM 2
29 
30 static const struct of_device_id dsicm_of_match[];
31 
32 struct dsic_panel_data {
33 	u32 xres;
34 	u32 yres;
35 	u32 refresh;
36 	u32 width_mm;
37 	u32 height_mm;
38 	u32 max_hs_rate;
39 	u32 max_lp_rate;
40 	bool te_support;
41 };
42 
43 struct panel_drv_data {
44 	struct mipi_dsi_device *dsi;
45 	struct drm_panel panel;
46 	struct drm_display_mode mode;
47 
48 	struct mutex lock;
49 
50 	struct backlight_device *bldev;
51 	struct backlight_device *extbldev;
52 
53 	unsigned long	hw_guard_end;	/* next value of jiffies when we can
54 					 * issue the next sleep in/out command
55 					 */
56 	unsigned long	hw_guard_wait;	/* max guard time in jiffies */
57 
58 	const struct dsic_panel_data *panel_data;
59 
60 	struct gpio_desc *reset_gpio;
61 
62 	struct regulator_bulk_data supplies[DCS_REGULATOR_SUPPLY_NUM];
63 
64 	bool use_dsi_backlight;
65 
66 	/* runtime variables */
67 	bool enabled;
68 
69 	bool intro_printed;
70 };
71 
72 static inline struct panel_drv_data *panel_to_ddata(struct drm_panel *panel)
73 {
74 	return container_of(panel, struct panel_drv_data, panel);
75 }
76 
77 static void dsicm_bl_power(struct panel_drv_data *ddata, bool enable)
78 {
79 	struct backlight_device *backlight;
80 
81 	if (ddata->bldev)
82 		backlight = ddata->bldev;
83 	else if (ddata->extbldev)
84 		backlight = ddata->extbldev;
85 	else
86 		return;
87 
88 	if (enable)
89 		backlight_enable(backlight);
90 	else
91 		backlight_disable(backlight);
92 }
93 
94 static void hw_guard_start(struct panel_drv_data *ddata, int guard_msec)
95 {
96 	ddata->hw_guard_wait = msecs_to_jiffies(guard_msec);
97 	ddata->hw_guard_end = jiffies + ddata->hw_guard_wait;
98 }
99 
100 static void hw_guard_wait(struct panel_drv_data *ddata)
101 {
102 	unsigned long wait = ddata->hw_guard_end - jiffies;
103 
104 	if ((long)wait > 0 && wait <= ddata->hw_guard_wait) {
105 		set_current_state(TASK_UNINTERRUPTIBLE);
106 		schedule_timeout(wait);
107 	}
108 }
109 
110 static int dsicm_dcs_read_1(struct panel_drv_data *ddata, u8 dcs_cmd, u8 *data)
111 {
112 	return mipi_dsi_dcs_read(ddata->dsi, dcs_cmd, data, 1);
113 }
114 
115 static int dsicm_dcs_write_1(struct panel_drv_data *ddata, u8 dcs_cmd, u8 param)
116 {
117 	return mipi_dsi_dcs_write(ddata->dsi, dcs_cmd, &param, 1);
118 }
119 
120 static int dsicm_sleep_in(struct panel_drv_data *ddata)
121 
122 {
123 	int r;
124 
125 	hw_guard_wait(ddata);
126 
127 	r = mipi_dsi_dcs_enter_sleep_mode(ddata->dsi);
128 	if (r)
129 		return r;
130 
131 	hw_guard_start(ddata, 120);
132 
133 	usleep_range(5000, 10000);
134 
135 	return 0;
136 }
137 
138 static int dsicm_sleep_out(struct panel_drv_data *ddata)
139 {
140 	int r;
141 
142 	hw_guard_wait(ddata);
143 
144 	r = mipi_dsi_dcs_exit_sleep_mode(ddata->dsi);
145 	if (r)
146 		return r;
147 
148 	hw_guard_start(ddata, 120);
149 
150 	usleep_range(5000, 10000);
151 
152 	return 0;
153 }
154 
155 static int dsicm_get_id(struct panel_drv_data *ddata, u8 *id1, u8 *id2, u8 *id3)
156 {
157 	int r;
158 
159 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID1, id1);
160 	if (r)
161 		return r;
162 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID2, id2);
163 	if (r)
164 		return r;
165 	r = dsicm_dcs_read_1(ddata, DCS_GET_ID3, id3);
166 	if (r)
167 		return r;
168 
169 	return 0;
170 }
171 
172 static int dsicm_set_update_window(struct panel_drv_data *ddata)
173 {
174 	struct mipi_dsi_device *dsi = ddata->dsi;
175 	int r;
176 
177 	r = mipi_dsi_dcs_set_column_address(dsi, 0, ddata->mode.hdisplay - 1);
178 	if (r < 0)
179 		return r;
180 
181 	r = mipi_dsi_dcs_set_page_address(dsi, 0, ddata->mode.vdisplay - 1);
182 	if (r < 0)
183 		return r;
184 
185 	return 0;
186 }
187 
188 static int dsicm_bl_update_status(struct backlight_device *dev)
189 {
190 	struct panel_drv_data *ddata = dev_get_drvdata(&dev->dev);
191 	int r = 0;
192 	int level = backlight_get_brightness(dev);
193 
194 	dev_dbg(&ddata->dsi->dev, "update brightness to %d\n", level);
195 
196 	mutex_lock(&ddata->lock);
197 
198 	if (ddata->enabled)
199 		r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
200 				      level);
201 
202 	mutex_unlock(&ddata->lock);
203 
204 	return r;
205 }
206 
207 static int dsicm_bl_get_intensity(struct backlight_device *dev)
208 {
209 	return backlight_get_brightness(dev);
210 }
211 
212 static const struct backlight_ops dsicm_bl_ops = {
213 	.get_brightness = dsicm_bl_get_intensity,
214 	.update_status  = dsicm_bl_update_status,
215 };
216 
217 static ssize_t num_dsi_errors_show(struct device *dev,
218 		struct device_attribute *attr, char *buf)
219 {
220 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
221 	u8 errors = 0;
222 	int r = -ENODEV;
223 
224 	mutex_lock(&ddata->lock);
225 
226 	if (ddata->enabled)
227 		r = dsicm_dcs_read_1(ddata, MIPI_DCS_GET_ERROR_COUNT_ON_DSI, &errors);
228 
229 	mutex_unlock(&ddata->lock);
230 
231 	if (r)
232 		return r;
233 
234 	return sysfs_emit(buf, "%d\n", errors);
235 }
236 
237 static ssize_t hw_revision_show(struct device *dev,
238 		struct device_attribute *attr, char *buf)
239 {
240 	struct panel_drv_data *ddata = dev_get_drvdata(dev);
241 	u8 id1, id2, id3;
242 	int r = -ENODEV;
243 
244 	mutex_lock(&ddata->lock);
245 
246 	if (ddata->enabled)
247 		r = dsicm_get_id(ddata, &id1, &id2, &id3);
248 
249 	mutex_unlock(&ddata->lock);
250 
251 	if (r)
252 		return r;
253 
254 	return sysfs_emit(buf, "%02x.%02x.%02x\n", id1, id2, id3);
255 }
256 
257 static DEVICE_ATTR_RO(num_dsi_errors);
258 static DEVICE_ATTR_RO(hw_revision);
259 
260 static struct attribute *dsicm_attrs[] = {
261 	&dev_attr_num_dsi_errors.attr,
262 	&dev_attr_hw_revision.attr,
263 	NULL,
264 };
265 
266 static const struct attribute_group dsicm_attr_group = {
267 	.attrs = dsicm_attrs,
268 };
269 
270 static void dsicm_hw_reset(struct panel_drv_data *ddata)
271 {
272 	gpiod_set_value(ddata->reset_gpio, 1);
273 	udelay(10);
274 	/* reset the panel */
275 	gpiod_set_value(ddata->reset_gpio, 0);
276 	/* assert reset */
277 	udelay(10);
278 	gpiod_set_value(ddata->reset_gpio, 1);
279 	/* wait after releasing reset */
280 	usleep_range(5000, 10000);
281 }
282 
283 static int dsicm_power_on(struct panel_drv_data *ddata)
284 {
285 	u8 id1, id2, id3;
286 	int r;
287 
288 	dsicm_hw_reset(ddata);
289 
290 	ddata->dsi->mode_flags |= MIPI_DSI_MODE_LPM;
291 
292 	r = dsicm_sleep_out(ddata);
293 	if (r)
294 		goto err;
295 
296 	r = dsicm_get_id(ddata, &id1, &id2, &id3);
297 	if (r)
298 		goto err;
299 
300 	r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_DISPLAY_BRIGHTNESS, 0xff);
301 	if (r)
302 		goto err;
303 
304 	r = dsicm_dcs_write_1(ddata, MIPI_DCS_WRITE_CONTROL_DISPLAY,
305 			(1<<2) | (1<<5));	/* BL | BCTRL */
306 	if (r)
307 		goto err;
308 
309 	r = mipi_dsi_dcs_set_pixel_format(ddata->dsi, MIPI_DCS_PIXEL_FMT_24BIT);
310 	if (r)
311 		goto err;
312 
313 	r = dsicm_set_update_window(ddata);
314 	if (r)
315 		goto err;
316 
317 	r = mipi_dsi_dcs_set_display_on(ddata->dsi);
318 	if (r)
319 		goto err;
320 
321 	if (ddata->panel_data->te_support) {
322 		r = mipi_dsi_dcs_set_tear_on(ddata->dsi, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
323 		if (r)
324 			goto err;
325 	}
326 
327 	/* possible panel bug */
328 	msleep(100);
329 
330 	ddata->enabled = true;
331 
332 	if (!ddata->intro_printed) {
333 		dev_info(&ddata->dsi->dev, "panel revision %02x.%02x.%02x\n",
334 			id1, id2, id3);
335 		ddata->intro_printed = true;
336 	}
337 
338 	ddata->dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
339 
340 	return 0;
341 err:
342 	dev_err(&ddata->dsi->dev, "error while enabling panel, issuing HW reset\n");
343 
344 	dsicm_hw_reset(ddata);
345 
346 	return r;
347 }
348 
349 static int dsicm_power_off(struct panel_drv_data *ddata)
350 {
351 	int r;
352 
353 	ddata->enabled = false;
354 
355 	r = mipi_dsi_dcs_set_display_off(ddata->dsi);
356 	if (!r)
357 		r = dsicm_sleep_in(ddata);
358 
359 	if (r) {
360 		dev_err(&ddata->dsi->dev,
361 				"error disabling panel, issuing HW reset\n");
362 		dsicm_hw_reset(ddata);
363 	}
364 
365 	return r;
366 }
367 
368 static int dsicm_prepare(struct drm_panel *panel)
369 {
370 	struct panel_drv_data *ddata = panel_to_ddata(panel);
371 	int r;
372 
373 	r = regulator_bulk_enable(ARRAY_SIZE(ddata->supplies), ddata->supplies);
374 	if (r)
375 		dev_err(&ddata->dsi->dev, "failed to enable supplies: %d\n", r);
376 
377 	return r;
378 }
379 
380 static int dsicm_enable(struct drm_panel *panel)
381 {
382 	struct panel_drv_data *ddata = panel_to_ddata(panel);
383 	int r;
384 
385 	mutex_lock(&ddata->lock);
386 
387 	r = dsicm_power_on(ddata);
388 	if (r)
389 		goto err;
390 
391 	mutex_unlock(&ddata->lock);
392 
393 	dsicm_bl_power(ddata, true);
394 
395 	return 0;
396 err:
397 	dev_err(&ddata->dsi->dev, "enable failed (%d)\n", r);
398 	mutex_unlock(&ddata->lock);
399 	return r;
400 }
401 
402 static int dsicm_unprepare(struct drm_panel *panel)
403 {
404 	struct panel_drv_data *ddata = panel_to_ddata(panel);
405 	int r;
406 
407 	r = regulator_bulk_disable(ARRAY_SIZE(ddata->supplies), ddata->supplies);
408 	if (r)
409 		dev_err(&ddata->dsi->dev, "failed to disable supplies: %d\n", r);
410 
411 	return r;
412 }
413 
414 static int dsicm_disable(struct drm_panel *panel)
415 {
416 	struct panel_drv_data *ddata = panel_to_ddata(panel);
417 	int r;
418 
419 	dsicm_bl_power(ddata, false);
420 
421 	mutex_lock(&ddata->lock);
422 
423 	r = dsicm_power_off(ddata);
424 
425 	mutex_unlock(&ddata->lock);
426 
427 	return r;
428 }
429 
430 static int dsicm_get_modes(struct drm_panel *panel,
431 			   struct drm_connector *connector)
432 {
433 	struct panel_drv_data *ddata = panel_to_ddata(panel);
434 	struct drm_display_mode *mode;
435 
436 	mode = drm_mode_duplicate(connector->dev, &ddata->mode);
437 	if (!mode) {
438 		dev_err(&ddata->dsi->dev, "failed to add mode %ux%ux@%u kHz\n",
439 			ddata->mode.hdisplay, ddata->mode.vdisplay,
440 			ddata->mode.clock);
441 		return -ENOMEM;
442 	}
443 
444 	connector->display_info.width_mm = ddata->panel_data->width_mm;
445 	connector->display_info.height_mm = ddata->panel_data->height_mm;
446 
447 	drm_mode_probed_add(connector, mode);
448 
449 	return 1;
450 }
451 
452 static const struct drm_panel_funcs dsicm_panel_funcs = {
453 	.unprepare = dsicm_unprepare,
454 	.disable = dsicm_disable,
455 	.prepare = dsicm_prepare,
456 	.enable = dsicm_enable,
457 	.get_modes = dsicm_get_modes,
458 };
459 
460 static int dsicm_probe_of(struct mipi_dsi_device *dsi)
461 {
462 	struct backlight_device *backlight;
463 	struct panel_drv_data *ddata = mipi_dsi_get_drvdata(dsi);
464 	int err;
465 	struct drm_display_mode *mode = &ddata->mode;
466 
467 	ddata->reset_gpio = devm_gpiod_get(&dsi->dev, "reset", GPIOD_OUT_LOW);
468 	if (IS_ERR(ddata->reset_gpio)) {
469 		err = PTR_ERR(ddata->reset_gpio);
470 		dev_err(&dsi->dev, "reset gpio request failed: %d", err);
471 		return err;
472 	}
473 
474 	mode->hdisplay = mode->hsync_start = mode->hsync_end = mode->htotal =
475 		ddata->panel_data->xres;
476 	mode->vdisplay = mode->vsync_start = mode->vsync_end = mode->vtotal =
477 		ddata->panel_data->yres;
478 	mode->clock = ddata->panel_data->xres * ddata->panel_data->yres *
479 		ddata->panel_data->refresh / 1000;
480 	mode->width_mm = ddata->panel_data->width_mm;
481 	mode->height_mm = ddata->panel_data->height_mm;
482 	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
483 	drm_mode_set_name(mode);
484 
485 	ddata->supplies[0].supply = "vpnl";
486 	ddata->supplies[1].supply = "vddi";
487 	err = devm_regulator_bulk_get(&dsi->dev, ARRAY_SIZE(ddata->supplies),
488 				      ddata->supplies);
489 	if (err)
490 		return err;
491 
492 	backlight = devm_of_find_backlight(&dsi->dev);
493 	if (IS_ERR(backlight))
494 		return PTR_ERR(backlight);
495 
496 	/* If no backlight device is found assume native backlight support */
497 	if (backlight)
498 		ddata->extbldev = backlight;
499 	else
500 		ddata->use_dsi_backlight = true;
501 
502 	return 0;
503 }
504 
505 static int dsicm_probe(struct mipi_dsi_device *dsi)
506 {
507 	struct panel_drv_data *ddata;
508 	struct backlight_device *bldev = NULL;
509 	struct device *dev = &dsi->dev;
510 	int r;
511 
512 	dev_dbg(dev, "probe\n");
513 
514 	ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
515 	if (!ddata)
516 		return -ENOMEM;
517 
518 	mipi_dsi_set_drvdata(dsi, ddata);
519 	ddata->dsi = dsi;
520 
521 	ddata->panel_data = of_device_get_match_data(dev);
522 	if (!ddata->panel_data)
523 		return -ENODEV;
524 
525 	r = dsicm_probe_of(dsi);
526 	if (r)
527 		return r;
528 
529 	mutex_init(&ddata->lock);
530 
531 	dsicm_hw_reset(ddata);
532 
533 	drm_panel_init(&ddata->panel, dev, &dsicm_panel_funcs,
534 		       DRM_MODE_CONNECTOR_DSI);
535 
536 	if (ddata->use_dsi_backlight) {
537 		struct backlight_properties props = { 0 };
538 		props.max_brightness = 255;
539 		props.type = BACKLIGHT_RAW;
540 
541 		bldev = devm_backlight_device_register(dev, dev_name(dev),
542 			dev, ddata, &dsicm_bl_ops, &props);
543 		if (IS_ERR(bldev)) {
544 			r = PTR_ERR(bldev);
545 			goto err_bl;
546 		}
547 
548 		ddata->bldev = bldev;
549 	}
550 
551 	r = sysfs_create_group(&dev->kobj, &dsicm_attr_group);
552 	if (r) {
553 		dev_err(dev, "failed to create sysfs files\n");
554 		goto err_bl;
555 	}
556 
557 	dsi->lanes = 2;
558 	dsi->format = MIPI_DSI_FMT_RGB888;
559 	dsi->mode_flags = MIPI_DSI_CLOCK_NON_CONTINUOUS |
560 			  MIPI_DSI_MODE_NO_EOT_PACKET;
561 	dsi->hs_rate = ddata->panel_data->max_hs_rate;
562 	dsi->lp_rate = ddata->panel_data->max_lp_rate;
563 
564 	drm_panel_add(&ddata->panel);
565 
566 	r = mipi_dsi_attach(dsi);
567 	if (r < 0)
568 		goto err_dsi_attach;
569 
570 	return 0;
571 
572 err_dsi_attach:
573 	drm_panel_remove(&ddata->panel);
574 	sysfs_remove_group(&dsi->dev.kobj, &dsicm_attr_group);
575 err_bl:
576 	if (ddata->extbldev)
577 		put_device(&ddata->extbldev->dev);
578 
579 	return r;
580 }
581 
582 static int dsicm_remove(struct mipi_dsi_device *dsi)
583 {
584 	struct panel_drv_data *ddata = mipi_dsi_get_drvdata(dsi);
585 
586 	dev_dbg(&dsi->dev, "remove\n");
587 
588 	mipi_dsi_detach(dsi);
589 
590 	drm_panel_remove(&ddata->panel);
591 
592 	sysfs_remove_group(&dsi->dev.kobj, &dsicm_attr_group);
593 
594 	if (ddata->extbldev)
595 		put_device(&ddata->extbldev->dev);
596 
597 	return 0;
598 }
599 
600 static const struct dsic_panel_data taal_data = {
601 	.xres = 864,
602 	.yres = 480,
603 	.refresh = 60,
604 	.width_mm = 0,
605 	.height_mm = 0,
606 	.max_hs_rate = 300000000,
607 	.max_lp_rate = 10000000,
608 	.te_support = true,
609 };
610 
611 static const struct dsic_panel_data himalaya_data = {
612 	.xres = 480,
613 	.yres = 864,
614 	.refresh = 60,
615 	.width_mm = 49,
616 	.height_mm = 88,
617 	.max_hs_rate = 300000000,
618 	.max_lp_rate = 10000000,
619 	.te_support = false,
620 };
621 
622 static const struct dsic_panel_data droid4_data = {
623 	.xres = 540,
624 	.yres = 960,
625 	.refresh = 60,
626 	.width_mm = 50,
627 	.height_mm = 89,
628 	.max_hs_rate = 300000000,
629 	.max_lp_rate = 10000000,
630 	.te_support = false,
631 };
632 
633 static const struct of_device_id dsicm_of_match[] = {
634 	{ .compatible = "tpo,taal", .data = &taal_data },
635 	{ .compatible = "nokia,himalaya", &himalaya_data },
636 	{ .compatible = "motorola,droid4-panel", &droid4_data },
637 	{},
638 };
639 
640 MODULE_DEVICE_TABLE(of, dsicm_of_match);
641 
642 static struct mipi_dsi_driver dsicm_driver = {
643 	.probe = dsicm_probe,
644 	.remove = dsicm_remove,
645 	.driver = {
646 		.name = "panel-dsi-cm",
647 		.of_match_table = dsicm_of_match,
648 	},
649 };
650 module_mipi_dsi_driver(dsicm_driver);
651 
652 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
653 MODULE_DESCRIPTION("Generic DSI Command Mode Panel Driver");
654 MODULE_LICENSE("GPL");
655